Health & Body Tables
Heart Rate Zone Table
Training zones are expressed as a percentage of maximum heart rate, which creates an immediate practical problem: nobody knows their maximum without a maximal test, and the standard estimate is a population average rather than a measurement. The formula 220 minus age is the one in widest use, and it carries a standard deviation of roughly 10 to 12 beats, meaning two people of the same age can have genuinely different maxima and both be completely normal.
A better estimate for adults came out of a 2001 meta-analysis that pooled hundreds of maximal tests: 208 minus 0.7 times age. It agrees with the classic formula around age 40 and diverges either side of it, overestimating for the young and underestimating for the old. The second table puts the two side by side so the size of the disagreement is visible rather than implied.
There is a second convention that matters when comparing figures across sources: zones can be set as a percentage of maximum heart rate or as a percentage of heart rate reserve, the latter being maximum minus resting heart rate, scaled and added back to resting. The reserve method is generally considered more accurate because it accounts for fitness, and it produces higher zone boundaries for the same stated percentage. Both are correct within their own convention, and quoting one while reading the other is the usual source of confusion.
The percentages in the first table are of estimated maximum, which is the convention most devices use by default. If your watch asks for a resting heart rate, it is almost certainly using the reserve method instead, and its zone boundaries will sit above the ones below.
Heart rate zones by age, from the 220 − age estimate
| Age | Estimated max | 50% (Very light) | 60% (Light) | 70% (Moderate) | 80% (Hard) | 90% (Maximum) |
|---|---|---|---|---|---|---|
| 20 | 200 | 100 | 120 | 140 | 160 | 180 |
| 25 | 195 | 98 | 117 | 137 | 156 | 176 |
| 30 | 190 | 95 | 114 | 133 | 152 | 171 |
| 35 | 185 | 93 | 111 | 130 | 148 | 167 |
| 40 | 180 | 90 | 108 | 126 | 144 | 162 |
| 45 | 175 | 88 | 105 | 123 | 140 | 158 |
| 50 | 170 | 85 | 102 | 119 | 136 | 153 |
| 55 | 165 | 83 | 99 | 116 | 132 | 149 |
| 60 | 160 | 80 | 96 | 112 | 128 | 144 |
| 65 | 155 | 78 | 93 | 109 | 124 | 140 |
| 70 | 150 | 75 | 90 | 105 | 120 | 135 |
| 75 | 145 | 73 | 87 | 102 | 116 | 131 |
Percentages are of estimated maximum heart rate, not of heart rate reserve. The reserve method adds resting heart rate into the calculation and gives higher figures for the same effort.
Two estimates of maximum heart rate, and the gap between them
| Age | 220 − age | 208 − 0.7 × age | Difference |
|---|---|---|---|
| 20 | 200 | 194 | 6 |
| 30 | 190 | 187 | 3 |
| 40 | 180 | 180 | 0 |
| 50 | 170 | 173 | -3 |
| 60 | 160 | 166 | -6 |
| 70 | 150 | 159 | -9 |
| 80 | 140 | 152 | -12 |
The classic formula overestimates maximum heart rate for older adults and underestimates it for younger ones. At 40 the two are within a beat; at 70 they differ by eight.
What each zone corresponds to
| Zone | % of maximum | Typical use | Talk test |
|---|---|---|---|
| Very light | 50–60% | Warm-up, cool-down, recovery sessions | Full conversation, no effort |
| Light | 60–70% | Fat-burning range, long easy sessions | Comfortable sentences |
| Moderate | 70–80% | Aerobic base, steady cardio | Short sentences only |
| Hard | 80–90% | Threshold work, tempo runs | Single words |
| Maximum | 90–100% | Intervals, sprint finish | No talking possible |
The talk test is a reasonable field check when a monitor is not available, and it agrees with the percentage zones surprisingly well for most people.
How to Use These Tables
- Find your zone: take the percentage of your estimated maximum. For a 40-year-old at 70%, that is 0.70 × 180 = 126 bpm.
- Sanity-check with the talk test: if you can hold a conversation you are below the moderate zone, whatever the monitor says.
- Compare like with like: establish whether a figure is a percentage of maximum or of reserve before comparing it against another source.
- Treat the maximum as an estimate with a 10 to 12 beat error bar, and adjust zones towards your own observed maximum once you have one.
Common Questions
How accurate is 220 minus age?
It is a population average with a standard deviation of about 10 to 12 beats, so roughly two thirds of people of a given age fall within that band. It is adequate for setting zones and inadequate for diagnosing anything.
What is heart rate reserve?
Maximum minus resting heart rate. The Karvonen method sets a target as resting plus the desired percentage of that reserve, which gives a higher figure than the same percentage of maximum because it starts from resting rather than from zero.
Why does my watch give different zones?
Either it is using the reserve method and you are reading a maximum-percentage table, or it has a measured maximum stored from a previous session. Check whether it has a resting heart rate recorded — if it does, the reserve method is likely in use.
Does medication change the zones?
Yes. Beta blockers and some other drugs lower heart rate directly, which makes percentage-of-maximum zones meaningless. Rate of perceived exertion, or a talk test, is the safer guide in that case.
Is a higher maximum heart rate better?
No. It is largely determined by age and genetics and does not indicate fitness. What improves with training is the heart rate at a given pace — fitter people do the same work at a lower rate.
More Health & Body Tables
Sources
- Physical activity guidelines and intensity — target heart rate — Centers for Disease Control and Prevention
- Tanaka, Monahan & Seals (2001): age-predicted maximal heart rate revisited — Journal of the American College of Cardiology
- Exercise intensity and heart rate reserve — Karvonen method — American College of Sports Medicine
Filed with Health calculations.